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Why do baseball players put a black mark under their eyes? – Althea, age 9, Edmonton, Alberta

Why do baseball players put a black mark under their eyes? – Althea, age 9, Edmonton, Alberta

Bottom of the ninth. Two outs. Bases loaded. The winning run is standing on third base. The pitcher winds up and throws. The batter swings and sends a high fly ball into the air. The center fielder races back, looks up at the sky and then says the sentence no baseball fan wants to hear: “I lost it in the sun.”

For baseball players, seeing the ball clearly can be the difference between making a game-winning catch and watching the winning run score. That is one reason many athletes put black marks under their eyes before a game.

Baseball, football and other outdoor athletes apply black stripes under their eyes because they hope it might reduce the glare from the sun or bright stadium lights. But the use of eye black comes down to tradition as much as it does science.

As an athletic trainer and professor who studies sports medicine and performance, I spend a lot of time thinking about how details like vision, sunlight and........

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